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I'm about to button up the 5.0. Please give me your preferred sealants for intake, valve covers, water pump etc.
 

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Intake:
Use Fel-Pro 1250 Intake Gaskets. Glue to heads using Gasgasinch. When is comes to ends, I have always used the cork gaskets which have an adhesive glue them to the block. I then put a dab of Permatex Ultra Black silicone where they meet the intake gaskets and a light coat of Ultra Black silicone on top of the cork before installing the intake. It looks neat and I have never had leak. Others run a bead of silicone only, your choice.

Water Pump:
Permatex Ultra Black silicone

Valve Covers:
Use cork gaskets only, seal them to the valve covers using Permatex Ultra Black silicone. On my cast aluminum valve covers, I have to trim in a few place to make them fit, do a trial fit. Do not put any type of sealant on the cork face which goes against the heads. I have used my covers on two different engines and removed the covers probably 5 or six times over the years and they never leaked.

Oil pan, fuel pump, water neck:
If not using a one piece gasket, thin coat Permatex Ultra Black silicone with gaskets
 

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Semi, I guess you'd say. I use that on the front water ports of the intake gaskets. Only sealer I will use on my antique motorcycles by the way. Good stuff. I don't normally advise coating gaskets with any kind of sealer but when you have to it is my choice.
I like to use RTV as little as possible. Dots in oil pan corners and timing cover dots, stuff like that. Big exception being the end corks for intakes, I hate those things. A big fat bead of RTV at each end of the intake and install the intake as quickly as possible makes for a solid seal that's the devil to take back apart later.

I posted at length recently (somewhere) about how when you apply RTV to a gasket and then assemble you make RTV "strings". These strings detach later to migrate into your oil pump strainer and/or the radiator end tank. BAD, very bad.
 

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Discussion Starter #6
"I posted at length recently (somewhere) about how when you apply RTV to a gasket and then assemble you make RTV "strings". These strings detach later to migrate into your oil pump strainer and/or the radiator end tank. BAD, very bad."

I've been taught that if you use enough silicone that it pushes out enough to see, it's too much.
 

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One way to look at it. I've known more than a few mechanics and engine builders I have respect for every one (if it's come up) says not to use RTV WITH gaskets, other than the aforementioned "dots". Even the factories use dots of RTV here and there. Timing covers on "modular" Ford engines come to mind. Speaking of OEMs, some even use RTV as a substitute for a gasket completely. First to pop into mind there would be FCA where they're been using an RTV that suspiciously resembles "The Right Stuff" on their minivan transmission pans. A nice trick but if you try it both surfaces must be meticulously clean and dry or it won't seal. RTV doesn't stick to fluid. Which is why they sell gaskets for those transmissions. After a fluid and filter change it's annoyingly difficult to keep the sealing surface fluid free long enough to successfully apply RTV.
 

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I followed the directions for all my gaskets and did not use any sealer on them except:
  1. Some of the Aviation gasket stuff on the water pump cover plate. Hated that stuff. what a mess!
  2. Some Permatex on the oil pan corners with the cork gaskets and rubber ends first go around. Did not leak. When I replaced the pan I used a 1 piece gasket with no sealer and it currently leaks out the front and back. Next oil change will drop pan and use some sealer at the corners
  3. For he intake manifold I first did Permatex Ultra Gray and seemed to work well. Had to tear down the motor 3 weeks later and I was surprised that the sealant was not cured on on the inside. Next go around I used the cork gaskets and coated them with Permatex as well as the block and manifold and assembled quickly. I liked that method better.
All this and on a new motor with limited run time, no leaks (except the oil pan)
 

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I've kept it simple and use just a thin coat of Permatex Ultra Blue on all my gaskets and a little daub on intake corners, have never had a leak, and it camouflaged well on a Ford Blue engine when I didn't wanna hafta blend or re-paint.
 
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